An aqueous synthetic resin dispersion consisting of (A) from 35 to 60% by weight of a synthetic resin prepared by free radical solution polymerization of a monomer mixture A1 and monomer mixture A2, wherein mixture A1 is (a) from 1.5 to 15% by weight of at least one C.sub.3-5 unsaturated monocarboxylic acid, maleic or itaconic acid or anhydride and half-esters of maleic acid or itaconic acid with a C.sub.1-8 ankanol or with glycol monoethers, (b) from 65 to 98.5% by weight of at least one C.sub.1-10 alkyl (meth)acrylate, and optionally at least one C.sub.11-20 alkyl (meth)acrylate (III), vinyl aromatic monomer (IV), mercaptosilane (V), and copolymerizable monomer (VI), and mixture A2 is (a) from 60 to 100% by weight of at least one monomer II, and optionally at least one monomer III, IV or VI and compound (V), with the proviso that more than 65% by weight of the sum total of A1 and A2 is accounted for by monomers II and an amount of compound V which differs from ) and is incorporated in the copolymer;(B) from 0.05 to 5% by weight of at least one epoxy group containing silane; and(C) at least one of ammonia and an organic amine; with the remainder being water and wherein the dispersion contains from 0 to 5% organic solvent.